Great songwriters are a dime a dozen in Nashville, but Kevin Gordon is an anomaly: a recovering poet who is better at selling outsider art than country hits, though Keith Richards and Levon Helm have sung his songs. The centerpiece here, “Colfax/Step in Time,” is a slow-burning 10-minute slice of life about a kid in the desegregated South, with Gordon’s talking-blues-meets-codeine-rap flow remembering his marching-band days and slyly rhyming “Kool and the Gang” and “Ku Klux Klan.” Meanwhile, the title track parses religious fervor in terms of politicians and human bombs. But the smarts on Gloryland never undercut the roots-rock rush. Dude’s a juke-joint professor emeritus.